When people acquire a second language (L2), do they benefit from analogical reasoning? Past research showed that people are likely to engage in analogical reasoning to support their L2 learning, yet it is unclear whether this process is explicit or only occurs automatically and implicitly. In the current study, English-speaking participants (N = 100) learned a miniature artificial language with grammatical markers that were either morphologically congruent or incongruent with English grammar. We then assessed participants’ acquisition of the artificial language and their explicit use of analogical reasoning. Acquisition was improved when the artificial language was structurally congruent with English, and was also better with participants who reported explicit analogical reasoning. This was especially pronounced for the ability to generate novel content. These findings provide evidence that learners acquiring a new language spontaneously leverage analogies with their existing languages, and this is especially beneficial when the analogies are recognized explicitly.